A study of the chemistry and metabolism of two aromatic amino acids and amines is proposed: a. An investigation of the metabolism of DOPA will be pursued which includes the generation of a possibly toxic trihydroxyphenylacetic acid formed by transamination of DOPA and hydroxylation of 3,4-dihydroxyphenylpyruvate. This study encompases a study of the incorporation of the reactive trihydroxy acid into proteins; the toxicity of the trihydroxyphenylacetic acid; the metabolic fate of this compound. The possible incorporation of DOPA into the primary structure of proteins will also be investigated. b. The study of "reduced" serotonin as a destructive inhibitor of serotonergic cells is proposed.